Prevalence, Natural History, Diagnosis, and Treatment of Food Allergy: A Systematic Review of the Evidence
May 7, 2010
A food allergy is an overreaction of the body's immune system that can be provoked by ingesting (or sometimes merely smelling) a particular food, most often milk, eggs, soy, wheat, nuts, or shellfish. The reactions involved can range from minor swelling of the lips and an itchy throat to potentially fatal anaphylactic shock.
At present, the only way to avert a reaction is to avoid the suspect food, which can require total dietary modification (potentially interfering with growth in children or necessitating costly milk substitutes), extreme vigilance, and major alterations in lifestyle. Given the serious implications of a suspected food allergy, then, it is vital that the tests used to diagnose these conditions be highly accurate, but a new review of the scientific literature on food allergies suggests that this is far from the case.
To assist the National Institute of Allergy and Infectious Diseases in its effort to promote the development of guidelines for the diagnosis and treatment of food allergies, researchers at the Southern California Evidence-Based Practice Center, a RAND Health center, conducted a systematic review of the entire body of research on the diagnosis, prevalence, natural course, prevention, and treatment of food allergy. Among their findings:
Progress in understanding the cause of food allergies, their prevalence, and how best to manage and even prevent them is clearly hampered by the need for better methods of diagnosis and higher-quality research studies.